TLV320AIC3109EVM-K: TLV320AIC3109

Hi Gene,  

have you taken a look at the EVM GUI?  there are tools at your disposal for setting up the filter response. 

best regards,

-Steve Wilson

Hi Steve,

Yes, I tried the GUI and set the Band Pass and tried loading the registers. I know I'm doing something wrong. I tried setting my Audio generator at the rejected frequencies and the amplitude level was the same as the band pass frequencies. I must have spent several hours trying different filters and settings but the output was still the same. I must be some how by passing the filters through the logic. The GUI is set for the 3104 because I'm using the 3109 single channel. I'll recheck the registers.

Gene

Gene, 

So the Digital filters tab will base the filter coefficients off of the ADC and DAC sample rates in the CLOCKS tab.  These are digital filters of course, so its important to set the sampling rate. 

Alternate options include:

1. use the TIBQ program.

2. Use Matlab to generate the filters, and follow the instructions in this application report to convert them to the accepted format

best regards,

-Steve Wilson

Steve,

I'm still trying to get the filters to work but still no luck. I tried some examples but I had the same experience. Could you provide me with a short command file that I could try go get this off the ground and put this to bed. The fs = 44.1Khz which is more than twice the Nyquist rate for the highest band pass of 3200Hz. The input  (band pass 300hz to 3200hz) at about 250 mv comes into the TLV320AIC3109EVM VIA J13 IN1 and the output is on left out J2A. Per the documentation I'm using the 3104 due to the single channel 3109. I've found several mistakes in the documentation which I'll submit documentation feedback later if I ever resolve my issue.

Gene

Gene, 

So your Fs is 44.1khz?  or is that your Fsref?   with such limited bandwidth, it seems necessary to have such a high sampling rate. 

Using TIBQ with an Fs of 44.1khz and cutoffs of 300hz and 3200Hz,  I have the following Biquad coefficients. 

BiQuad 1:

N0 = 0x7C2F

N1 = 0x83D1

N2 = 0x7C2F

D0 = 0x7C20

D1 = 0x8784

BiQuad 2:

N0 = 0x04FC

N1 = 0x04FC

N2 = 0x04FC

D0 = 0x57A2

D1 = 0xBCCA

I have not tested these on an EVM as I do not have my audio analyzer with here.  but give those a shot and let me know what you see. 

best regards, 

-STeve Wilson

Hi Steve,

Unfortunately this didn't work. Would it be possible for you to give me the register values that is used for the EVM board. I tried for several hours/days to get this to work but with no luck. The values could not be placed as an input in the 3104 GUI. Also per the data sheet for the filter values states:

The 16-bit integer contained in the MSB and LSB registers

for this coefficient are interpreted as a 2's-complement

integer with possible values ranging from –32,768 to 32,767.

This would not work with the GUI. If you could help me with the final hex values for each register I'd appreciate it.

Thank you, Gene